Keith Chuvala, a United Space Alliance contractor, manager of the Space Operations Computing (SpOC) for NASA, and leader of the iSS's Laptops and Network integration Teams, recently explained that NASA had decided to move to Linux for the iSS's PCs. "We migrated key functions from Windows to Linux because we needed an operating system that was stable and reliable - one that would give us in-house control. So if we needed to patch, adjust, or adapt, we could."
Specifically, the iSS astronauts will be using computers running Debian 6. Earlier, some of the on-board computers had been using Scientific Linux, a Red Hat Enterprise Linux (RHEL) clone. While not the newest version of Debian, Debian 7 has just been released, Debian is nothing if not well-tested and reliable.
While Linux has been used on the iSS ever since its launch (PDF link) and for NASA ground operations almost since the day Linus Torvalds created it, it hasn't seen that much use on PCs in space. "Things really clicked," said Chuvala in an interview, "after we came to understand how Linux views the world, the interconnectedness of how one thing affects another. You need that worldview. i have quite a bit of Linux experience, but to see others who were really getting it, that was exciting."
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